<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        .box {
            width: 500px;
            height: 500px;
            border: 1px solid #000;
            display: flex;
            /* 水平垂直居中 */
            /* justify-content: center;
            align-items: center; */
            /* 两端有相同的距离，中间是两端的一倍*/
            /* justify-content: space-around; */
            /* 两端对齐，中间相等 */
            /* justify-content: space-between; */
            /* 间隔的距离相等*/
            /* justify-content: space-evenly; */
            /* 决定主轴的放向 */
            /* flex-direction: column; */
            /* align-items: flex-end; */
        }

        .left {
            width: 100px;
            /* flex: 1; */
            height: 100px;
            background-color: aqua;
            display: inline-flex;
            justify-content: space-between;
        }

        .moddle {
            height: 150px;
            width: 100px;
            background-color: aquamarine;
        }

        .right {
            /* flex: 1; */
            width: 100px;
            height: 130px;
            background-color: blueviolet;
            /* align-self: flex-start;   */
        }

        .div1 {
            background-color: brown;
            width: 20px;
            height: 20px;
        }

        .div2 {
            background-color: burlywood;
            width: 20px;
            height: 20px;
        }
    </style>
</head>

<body>
    <div class="box">
        <div class="left">
            <div class="div1">1</div>
            <div class="div2">2</div>
        </div>
        <div class="moddle">中</div>
        <div class="right">右</div>
    </div>
</body>

</html>